Implemented set_name

Author: DOhlsson

src/sys/prctl.rs

@@ -6,11 +6,12 @@
 //! For more documentation, please read [prctl(2)](https://man7.org/linux/man-pages/man2/prctl.2.html).
 
 use crate::errno::Errno;
+use crate::sys::signal::Signal;
 use crate::Result;
 
-use crate::sys::signal::Signal;
-use libc::{c_int, c_ulong};
+use libc::{c_char, c_int, c_ulong};
 use std::convert::TryFrom;
+use std::ffi::{CStr, CString};
 
 pub use self::PrctlOption::*;
 
@@ -150,17 +151,8 @@ pub fn set_child_subreaper(attribute: bool) -> Result<()> {
 pub fn get_child_subreaper() -> Result<bool> {
     // prctl writes into this var
     let mut subreaper: c_int = 0;
-    println!("Addr: {:p}", &mut subreaper);
 
-    let res = unsafe {
-        libc::prctl(
-            PR_GET_CHILD_SUBREAPER as c_int,
-            &mut subreaper,
-            0,
-            0,
-            0,
-        )
-    };
+    let res = unsafe { libc::prctl(PR_GET_CHILD_SUBREAPER as c_int, &mut subreaper, 0, 0, 0) };
 
     Errno::result(res).map(|_| subreaper != 0)
 }
@@ -239,7 +231,6 @@ pub fn set_pdeathsig<T: Into<Option<Signal>>>(signal: T) -> Result<()> {
 pub fn get_pdeathsig() -> Result<Option<Signal>> {
     // prctl writes into this var
     let mut sig: c_int = 0;
-    println!("Addr: {:p}", &mut sig);
 
     let res = unsafe { libc::prctl(PR_GET_PDEATHSIG as c_int, &mut sig, 0, 0, 0) };
 
@@ -251,3 +242,28 @@ pub fn get_pdeathsig() -> Result<Option<Signal>> {
         Err(e) => Err(e),
     }
 }
+
+/// Set the name of the calling thread (max 15 bytes)
+pub fn set_name(name: &String) -> Result<()> {
+    let name = CString::new(name.as_bytes()).unwrap();
+
+    let res = unsafe { libc::prctl(PR_SET_NAME as c_int, name.as_ptr(), 0, 0, 0) };
+
+    Errno::result(res).map(drop)
+}
+
+/// Return the name of the calling thread
+pub fn get_name() -> Result<String> {
+    let buf = [32u8; 16];
+
+    let res = unsafe { libc::prctl(PR_GET_NAME as c_int, &buf, 0, 0, 0) };
+
+    let ptr = buf.as_ptr() as *const c_char;
+    let cstr = unsafe { CStr::from_ptr(ptr) };
+    let name = match cstr.to_str() {
+        Ok(name_str) => name_str.to_owned(),
+        Err(_) => return Err(Errno::EINVAL),
+    };
+
+    Errno::result(res).map(|_| name)
+}

test/sys/test_prctl.rs

@@ -56,3 +56,16 @@ fn test_get_set_pdeathsig() {
     let sig = prctl::get_pdeathsig().unwrap();
     assert_eq!(sig, Some(Signal::SIGUSR1));
 }
+
+#[test]
+fn test_get_set_name() {
+    let long_name = String::from("0123456789abcdefghijklmn");
+    prctl::set_name(&long_name).unwrap();
+    let res = prctl::get_name().unwrap();
+    assert_eq!(&long_name[..15], res);
+
+    let short_name = String::from("01234567");
+    prctl::set_name(&short_name).unwrap();
+    let res = prctl::get_name().unwrap();
+    assert_eq!(short_name, res);
+}